This planning grant seeks to plan and design, and to generate the documentation necessary for a multicenter randomized controlled trial of a multimodality intervention for mobility limitation in older Americans (The MultiMod Mobility Trial) Recent discussions between the NIA and the CTSA Consortium led to the identification of mobility limitation in the elderly as a primary target for an intervention trial because of its hig prevalence, its grievous impact on an individual's health, survival, and quality of life, and its socioeconomic consequences. Multimodality interventions are particularly appropriate for complex geriatric syndromes, such as mobility limitation, because these syndromes are multifactorial in their etiology and because multimodality interventions provide a closer approximation of clinical care in geriatrics, and have the potential of providing a more favorable risk: benefit ratio and benefiting a broader segment of the population than unimodality interventions. A multidisciplinary working group favored an initial trial in a post-acute event model, focusing on older adults, who have sustained a hip fracture, have completed their initial rehabilitation in a subacute care setting, but have persistent mobility limitation. This indication has several advantages, enumerated in the application. Multimodality intervention trials in mobility limited older individuals are inherently challenging because of the complexities of study design, the difficulties in subject recruitment, the high burden of comorbid conditions, and high costs. Therefore, a planning grant is necessary to lay the foundation of such a complex trial by facilitating resolution of issues related to study design, subject recruitment, selection of interventions and outcomes, and protocol development. The specific aims are to: 1. Establish the necessary expert collaborations and infrastructural resources for trial's implementation. 2. Finalize the design of a multimodality intervention trial in older individuals with mobility limitaion by establishing the specific indication for which the trial will be conducted, the subject inclusio and exclusion criteria, the method of subject allocation, the components of the multimodality intervention, the intervention duration, the trial's primary and secondary outcomes, sample size, and the analytical plan. 3. Prepare the documentation to support trial implementation by developing a study protocol, the methods for data collection, and a Data and Safety Monitoring Plan; by obtaining commitments to supply pharmaceutical products; and by planning the Manual of Operations. 4. To determine the recruitment potential for the trial. These aims will be accomplished by organizing conference calls of the designated task forces, two facetoface meetings, and by analyses of secondary databases, and consultation with experts in specific content areas. The product of the planning grant will be an NIH application to conduct the trial. An interdisciplinary team with substantial expertise in the relevant content areas, the public health importance of mobility limitation, and substantial work that has already been accomplished by the team during the past two years should ensure the successful accomplishment of the stated aims.